The invention relates to an apparatus comprising a drive arrangement for winding an information carrier in the form of a tape between a first reel hub and a second reel hub and vice versa, which apparatus comprises a motor having a motor shaft which can be driven in a positive direction of rotation and an opposite negative direction of rotation, at least one motor wheel coupled to the motor shaft for rotation in each of the directions of rotation, a first drive spindle for driving the first reel hub and provided with at least one spindle wheel, a second drive spindle for driving the second reel hub and provided with at least one spindle wheel, a first, a second, a third and a fourth transmission device, respectively, comprising a first, a second, a third and a fourth set of drive wheels, at least some of said drive wheels being movable relative to one another, which sets each include at least one of the motor wheels and one of the spindle wheels, which transmission devices are switchable between inactive and active states and which respectively serve for the motor shaft to drive the first drive spindle with a first transmission ratio, the second drive spindle with a first transmission ratio, the first drive spindle with a second transmission ratio, the second drive spindle with a second transmission ratio, switching mechanisms for switching the first, the second, the third and the fourth transmission device between active and inactive states, a rotatable cam disc having guide surfaces which cooperate with at least one switching mechanism, a cam disc drive wheel for driving the cam disc, in which apparatus the cam disc can be set to a plurality of stop positions which correspond to one of the states of one of the transmission devices, while at the same time the other transmission devices are in their inactive states.
Such an apparatus is known from EP 0,488,714 A1 (herewith incorporated by reference). The known apparatus serves for reproducing and, if desired, also recording signals from/on the magnetic tape of a Compact Cassette. The cassettes are suitable for recording and reproducing information both during transport of the tape in a first and in an opposite second tape Wansport direction. The known apparatus has a reproduction mode for each of said transport directions, for which it is not necessary to remove the cassette from the apparatus. The apparatus also has a fast wind mode for each of the transport directions for rapidly proceeding to a given piece of information on the tape. All the tape transport modes can be selected by the electrical control of the motor for rotation in one of the two directions of rotation in combination with the electrical energisation of an electromagnet. How and in what manner these modes are selected in the known apparatus will be described in detail hereinafter.
The cam disc of the known apparatus serves as a driving element for certain switching movements. For this purpose the cam disc has a plurality of curved guide surfaces which locally make an angle with the tangent to the cam disc. Owing to this angle a non-rotating element which is in contact with a guide surface will be moved upon a given rotation of the cam disc. The known apparatus further comprises an electromagnet which cooperates with the cam disc via a lever.
By energising the electromagnet in the case of a positive direction of rotation of the motor shaft the cam disc is rotated from a first stop position, in which the first and the second transmission device are in an inactive state, to a second stop position. Thus, the first transmission device is switched to the active state by cooperation of a first switching mechanism with a first guide surface. As a result of the actuation of the electromagnet the cam disc is slightly rotated, after which the cam disc drive wheel meshes with a toothed portion on the cam disc. When the motor shaft is driven in the positive direction of rotation this cam disc drive wheel rotates the cam disc in the same direction until a recess in the toothed portion of the cam disc is situated at the location of the cam disc drive wheel, where the second stop position of the cam disc is reached. As a result of the cooperation of the first switching mechanism with the first guide surface of the cam disc the motor shaft is brought into driving relationship with the first drive spindle via the first set of drive wheels. In the case of a positive direction of rotation of the motor shaft the motor shaft will drive the first drive spindle with the first transmission ratio.
By energising the electromagnet two times with a break while the motor shaft rotates in a positive direction the cam disc will be rotated from the first stop position to the second stop position, the second transmission device being set to the active state by cooperation of the first switching mechanism with a second guide surface. To start this rotation the electromagnet is energised a first time. The second energisation sets the first switching mechanism, via a lever which is driven by a third guide surface of the cam profile, to a position in which the first switching mechanism cooperates with the second surface of the cam profile. Owing to the cooperation of the first switching mechanism with the second guide surface of the cam profile the motor shaft is brought into driving relationship with the second drive spindle via the second set of wheels. As a result of this, the motor shaft drives the second drive spindle with the first transmission ratio in the case of a positive direction of rotation of the motor shaft.
By energising the electromagnet in the second stop position the cam disc is rotated into the first stop position in a manner similar to that described above. As a result of this rotation the first switching mechanism is returned to its original state by cooperation with the cam disc. Thus, the first transmission device or the second transmission device is set from the active to an inactive state.
The third transmission device can be set to the active state by means of a so-called fiction clutch by driving the motor shaft in the negative direction of rotation. The fiction clutch comprises a switching wheel supported on a movable element. This element is positioned by a friction force produced by a friction which has been provided deliberately between a rotating drive wheel and its environment. The direction of the force depends on the direction of rotation of the drive wheel, so that the switching wheel is brought into or out of mesh with a subsequent drive wheel depending on this direction of rotation. The fiction clutch forms part of the third transmission device, which is activated by driving the motor shaft in the negative direction of rotation, so that the motor shaft is brought into driving relationship with the first drive spindle via the third set of wheels. In the case of a negative direction of rotation of the motor shaft the motor shaft drives the first drive spindle with a second transmission ratio.
The fourth transmission device can be set to the active state by driving the motor shaft in the positive direction of rotation when the cam disc is in the first stop position. In the other angular positions of the cam disc this is impossible owing to the cooperation of a second switching mechanism with a second set of guide surfaces on the cam disc. This second switching mechanism comprises a slide member and a fiction clutch. When the cam disc is in said first stop position the second set of guide surfaces has positioned the slide member in such a manner that the fiction clutch is activated by a positive direction of rotation of the motor shaft. Thus, the motor shaft is brought into driving relationship with the second drive spindle via the third set of wheels, so that the motor shaft drives the second drive spindle with the second transmission ratio.
To locate a piece of information on the tape the user wishes to use the first transmission ratio for the reproduction of the information on the tape and, subsequently, the second transmission ratio to proceed with a higher speed to another location at the tape. For successively driving the first drive spindle with these two transmission ratios it is each time necessary to change the direction of rotation of the motor shaft in the known apparatus, which requires time. Moreover, in operation there is a continual loss of energy in the said apparatus owing to the deliberately applied friction in the friction clutch. In addition, energy is dissipated in that several gear wheels rotate without these wheels contributing to the transport of the tape, which may also produce undesirable noise. When an independent current source such as dry batteries or a storage battery is used this results in an unnecessary reduction of the playing time of the known apparatus.